Figure 7. Self-charging mechanism of the ZnO@Mo-Fe-MnO2 NA based SCSPC. (a) The original state of the device without external forces. (b) The potential difference created by the external force drove the mobility of the electrolyte ions. (c) The potential difference resulting from the residual stress caused the electrolyte ions to migrate again.(d) A new electrochemical equilibrium was reached. (e)The positive and negative potentials disappeared, and the counter migration of electrolyte ions occurred and returned to the original states.